This article lists non-canon information. Additions to the brief character definitions listed here should include only a list of appearances and a short definition of their status as of their last appearance in this series. Other non-canon appearances will not be listed here. If you want to read about their canon information, their names will be hyperlinked to their main article. The specifics of non-canon characters' appearances should be listed in the character section of each audio production, novel, comic book, or game in which they played a role.

Sisko, who first appeared in the novelization Emissary, was in nearly all DS9 publications until the so-called "relaunch", when he was removed from the series due to his fate revealed in DS9: "What You Leave Behind". He returned from that hiatus in Unity and takes leave from Starfleet. In Rough Beasts of Empire, Sisko returns to Starfleet to fight the Borg and is later assigned to command the USS Robinson, a Galaxy-class vessel.

Bajoran Militia liaison and XO of DS9. Kira was assigned to the station while a major in rank, and she eventually was promoted to colonel, and later was made station CO. Kira was awarded a commission as a Starfleet commander in 2376 by Admiral Leonard James Akaar.

Kira, who first appeared in the novelization Emissary, has appeared in nearly all DS9 publications to date.

Command division Starfleet officer serving aboard DS9. Ezri joined the crew as an ensign, as the station's assistant counselor. She was soon promoted to lieuenant junior grade, and, after the conclusion of the Dominion War, she decided to pursue a career as a command officer. Ezri departs Deep Space 9 for the USS Aventine, a ship she later becomes captain of.

Starfleet lieutenant junior grade assigned as DS9's operations chief. Nog grew up, as a Ferengi errand boy, aboard DS9, before entering Starfleet Academy in 2372. He served as Chief O'Brien's apprentice while a cadet, eventually earning a field promotion to ensign. Nog was promoted to lieutenant per the captain's final orders, before Sisko vanished in late 2375.

Vaughn has been offered promotions many times over the years, but in keeping with his mission with Special Ops, prefers to remain a commander in order to keep a low profile. Even so, officers all the way to the rank of admiral routinely rely on Vaughn for advice, and generally do not attempt to pull rank on him.

He has a strained relationship with his daughter, Starfleet Ensign Prynn Tenmei, ever since an incident with Prynn's mother Ruriko, who had been assimilated by the Borg seven years prior to the novels under his command. On the Gamma Quadrant missions their relationship was under repair until Ruriko's assimilated corpse was found. Ruriko attacked her daughter and attempted to assimilate her, and Elias was forced to kill Ruriko in defense. Prynn blamed him for months for this incident. Vaughn eventually accepted a promotion to the rank of captain and for a time commanded Deep Space Nine and later a starship before perishing due to injuries sustained during the Borg invasion.

Vaughn was 101 years old when he first appeared, and was in excellent physical health, implying that Humans routinely lived much longer in Trek's future.

Ensign Tenmei is the new Defiantflight controller, and Cmdr. Vaughn's daughter. She blames her father for the death of her mother, who was believed killed during an away mission he sent her on. She is named for T'Prynn of Vulcan.